They will pick it up later.
Room service tray outside door.
That s exactly what you do.
In a nice hotel you are paying for service and ambiance.
The ambiance for all guests is important.
Guests who elect to clean up themselves can place their dishes and dinner accoutrements on the delivery cart and place it in the hallway outside the door or in an out of the way spot in the room.
Leave th tray outside by the door.
Yes i agree most people just put the tray in the hall outside the door but that s not correct especially in a higher end hotel or resort.
When one orders room service they after finishing their snacky bits or meals put the dirty dishes on the tray and then put it in the hallway directly outside their room.
If for some reason i must put a tray outside e g.
In some hotels guests can call the room service attendant back to the room to clear the meal and remove the dishes.
If it is nearly room cleaning time in the morning then you can leave it in the room.
The standard etiquette for disposing of a service tray is to put it outside the door with or without calling to have it picked up but it might depend on the circumstances e g if i had ordered a late night dinner or breakfast then i would just leave it in the room for it removed when the room is serviced.
Upscale hotels really do prefer if you call to have the tray picked up.
Soiled dishes and equipment in corridors are unsightly and indicate a poorly run room service department.
The guest leaves the tray outside the door.